Bruno is proof that we have come a long way from the Gay News trial

Once again, events in the film world have supplied me with another not-especially-Proustian rush back into the past. Sacha Baron Cohen's very funny new film Bruno has an aggressively gay hero who uncovers various dark strands of homophobia in modern America. If anything typifies the way in which things really have changed in British public life over the past 30 years, it is surely our attitude to homosexuality, and now even the Conservative leader is offering a mea culpa on the issue of Section 28. David Cameron said: "We got it wrong. It was an emotional issue. I hope you can forgive us." I can imagine Bruno rasping that sentence in his heavy mock-Viennese accent.

Weirdly, the film, with its in-your-face gay gags, brought back memories of the first thing I ever had published in a newspaper. It was in the summer of 1977, and it was a letter to, erm, the Daily Mail. Perhaps I should qualify this somewhat. It was a letter to the Junior Mail letters section that appeared in that paper on Saturdays, intended for letters from kids. And my letter was about Mary Whitehouse and her private prosecution of Gay News and the subsequent blasphemy trial. Gay News was fined £1,000 and the editor, Denis Lemon, received a fine of £500 and a nine-month suspended prison sentence, subsequently overturned on appeal. It was a key moment in the 70s that doesn't get remembered much: the nasty, unfunny, depressing, vindictive and bloody awful 70s.

I left the cinema after Bruno, took the underground to the British Library's newspaper archive in Colindale, and in a spirit of masochism ordered up the Mail's microfilm roll for July 1977 and re-read my earnest letter about Gay News for the first time in 30 years. Here it is, in all its stately glory, under the headline: "I call this censorship".

After reading of the recent court case involving the publication by Gay News, the newspaper for homosexuals, of a poem describing a Roman centurion's love for the body of Christ, the only aspect of the whole affair which disgusted me was the fact that officious busybodies like Mary Whitehouse can still manage to invade the freedom of the press in Britain in this way. As I see it, Gay News has every right to publish their poem, just as the British citizen has every right to agree or disagree with it. The poem's suppression smacks of Stalinesque censorship. Yours, Peter Bradshaw (aged 15)

I shall complete the agony by revealing that I received a postal order for £1, which I rushed out and radically spent on the Sex Pistols' single God Save the Queen, with the famous picture sleeve. The letter is of course fantastically callow; I'm not sure what "agreeing" or "not agreeing" with a poem exactly means, and, though I like to think that the Mail's subs added that explanatory line about Gay News being a "newspaper for homosexuals", I have a horrible feeling that I wrote it myself. Perhaps this is something else that would benefit from Bruno reading it aloud.

Maladroit it may have been, but I have to say that I was and in fact still am rather proud of having done this. In fact, it is one of the few things that I did as a teenager that doesn't cause me to cringe with horror. Speaking up for gay rights was not a particularly common occurrence in those days, even on the left, and certainly not in newspapers. The Mail appeared to tolerate this sort of thing in the kids' section – I don't think my letter would have got into print had it been addressed to the grownups' pages. Web 2.0 didn't exist in those days; if it did, my letter might have been circulated and I could, I guess, have been bullied at school. As it was, my letter became chip paper like everything else and no one had the smallest clue that I had written it.

But oh God, how awful the Gay News trial was: one of the meanest, nastiest, pettiest things ever to have occurred in British public life, and one of the unfunniest things about that remarkably unfunny decade. Francis Wheen wrote that if the 60s were a wild weekend, and the 80s were a hectic day in the office, then the 70s were a long Sunday afternoon and evening: filled with boredom and vague, nagging dread. The Gay News row epitomised the sheer loathesomeness of the time, a Life On Mars that was no Life at all. Graham Chapman was a friend and investor in Gay News, and the experience undoubtedly spurred him on to help create Monty Python's Life of Brian, and generally stick it to the Christian right.

How glad I am to be living in the era of Bruno, and not the pinched era of Mrs Whitehouse and the Gay News trial. In pop cultural terms, we've never had it so good.